DISEASES AFFECTING THE SKIN 347 
Liberian cases, Sarcoptes scabiei was found by Theiler upon microscopical ex- 
amination of scrapings from the skin, but no other organisms were observed in 
connection with the condition. Dr. Shattuck made the clinical observation that 
in Liberia the distribution of the lesions of scabies differed from that of Europe 
and the United States. The lesions in Liberia are commonly seen upon the lower 
limbs, whereas in Europe and the United States they characteristically stop at 
the knee. He also made the same observation in Amazonia. 
Craw-craw in another form was also observed in Liberia with papular and 
in some instances older vesicular lesions. In Case 184 (No. 270) of this 
nature the distribution of the lesions was particularly over the elbows, a few 
over the posterior surface of the arms, and over the abdomen and very profuse 
over the buttocks. The lesions generally consisted of dried-up vesicles or pap- 
ules from 2 to 3 mm. in diameter and numerous smaller pustules. When these 
were scraped with a knife, very shallow ulcers were revealed. Many microscopi- 
cal preparations were made from the base of the papules and pustules and from 
the scrapings of the shallow ulcers. Pieces of the skin containing the papules 
were hardened in alcohol and Zenker’s solution. Examination of the film 
preparations from the lesions showed large numbers of cocci and polymorphonu- 
clear leucocytes, the micro-organisms being both intra- and extra-cellular. No 
spirochaetes nor Blastomyces were observed and no organisms were seen within 
the epithelial cells. Sections of the tissues examined after our return show mili- 
ary abscesses occurring in the epidermis (No. 271) lying beneath the stratum 
granulosum and the mucous layer. The papillae are pushed downward by the 
exudate and their upper surfaces are infiltrated and necrotic. The stratum 
corneum is preserved over the abscesses, as may be seen from the illustration. 
The abscess cavity consists of an albuminous exudate, staining lightly pink, 
occupying the area just below the stratum granulosum. Almost no cells what- 
ever are present in it. Below this area there is one very richly infiltrated with 
polymorphonuclear leucocytes, endothelial cells and a few fibroblasts. Cocci, 
both free and within polymorphonuclear leucocytes, are present in large numbers 
in this area. Sometimes these micro-organisms are in chains of four or five. 
They do not extend very deeply into the papillae. At the sides of the abscesses 
cocct may be seen within the lymph spaces and small blood vessels or papillae. 
About these vessels there is sometimes slight endothelial proliferation, and in 
their vicinity a dense infiltration with endothelial cells and polymorphonuclear 
leucocytes, the former predominating in the deeper layers of infiltration. The 
deeper portions of the corium are particularly free from infiltration. This form 
of craw-craw is certainly of bacterial origin and the micro-organism shown in 
the photomicrograph is obviously the etiological factor in the lesions (No. 272). 
Rodhain ! has recently reported upon cases of papular dermatitis, epidemic 
in the Belgian Congo in which the lesions started first as small circumscribed 
papules which within twelve days grew to a diameter of 12 to 14 mm. and were 
then raised 2 to 3 mm. above the surrounding skin. A deep vesicle then appeared 
which later broke down and left an ulcer roughly 1 em. in diameter. This ulcer 
1 Rodhain: Ann. Soc. Belge de Méd. Trop. (1928), VIII, 325. 
